1. Field of the Invention
The present invention relates to equipment which is employed for detecting the flow quantity and, more particularly, to a sensor for detecting the flow quantity of fuel supplied to a fuel injection system. As conventionally used in this art, the "flow quantity" of fuel is the amount of fuel supplied to the cylinder of an engine per stroke of a plunger of an injection pump.
2. Statement of the Prior Art
Various efforts have been made to develop systems used for regulation of internal combustion engines, particularly for electronic regulation systems applicable to regulation of internal combustion engines for the ultimate purposes of making the exhaust gas of such engines cleaner and improving the combustion efficiency of such engines. For the foregoing purposes, such systems as described above absolutely require various types of detectors or sensors including a sensor which is applicable to continuous detection or measurement of the quantity of fuel which is injected to an internal combustion engine.
Various types of sensors for measurement of the flow quantity of fuel and which can be mounted on an automobile have been developed and are available in the prior art. Among the flow meters available in the prior art, a turbine type flow meter is recognized as most excellent from the realistic viewpoints. Unfortunately, however, the turbine type flow meter is accompanied by drawbacks including (1) a rather large external dimension thereof, (2) a limitation concerning the means to arrange the meter inside an automobile, and (3) a limitation for the minimum flow quantity for which the measurement is allowed. As a result, it is determined that a turbine type flow meter available in the prior art is not necessarily appropriate for application particularly to small sized automobiles.